In the pursuit of reducing the overall weight of the wind turbine mass, Moventas’ engineers have discovered an innovative power / density concept based on proven designs. By designing a gearbox compact and extremely lightweight, our state-of-the-art unit provides a significant reduction of tower head mass. The need for drivetrain space in the axial direction is equally reduced by the power density concept. All reaction forces can be transmitted to the nacelle structure in an optimal way. The concept also ensures that no need for separate support structures for the generator.
Torque density is used to measure gear performance. It states the level of allowable torque per kilogram of gear material. Lowering the mass also influences gear dimensions, so density correlates with mass. Moventas’ expert gear design skills and application-know-how with improved materials allow higher gear torque densities for new gear unit designs.
Noise & vibration
Moventas says it has successfully reduced the noise level of its gearboxes by improving tooth accuracy and choosing the optimal geometry and profile. Theoretical evaluation as well as on-site testing can eliminate harmful resonance sounds of the structural elements. To achieve noiseless wind power, the gear unit must not vibrate. Therefore, our gear units are especially designed to prevent vibrations from passing through the gearbox fixing points to the foundation of the wind power plant.
Verification
The Moventas product portfolio is the result of proven technology including modular components for all drivetrains. Moventas planetary gear consists of our special know-how of, for example, integrated bearings, case hardened ring wheels, and Flexspider technology. Our product concepts are based on approved methods of regulatory agencies.
All the gear units are verified by tests and measurements. Moventas has vast experience from prototype testing and qualification. During the last decade we have performed over one hundred modern wind turbine gear prototype test in MW class alone. Typically prototype gear units go through lifecycle and cold climate chamber tests. We also use virtual prototype environment to define drivetrain dynamics.
All gear units serviced at Moventas Service Centers are test run prior to delivery to ensure reliable operation. Moventas field service also has the same high quality standards as the Service Centers.
All new company gearboxes and replacements undergo extensive test runs. Special attention is always paid to bearing and oil temperatures, oil leakage and noise levels.
Testing up to 10 MW
Company Technology Center in Jyväskylä, Finland, researches the dynamic behaviour of gear unit components and enables testing of a wind turbine gearbox up to ten megawatts. At the center, we can test prototype units under all load conditions to qualify their noise and vibration performance. Our engineers also perform extensive modal impact testing to ensure that resonances of a gear unit do not match the excitation frequencies of the surrounding structure or gear mesh frequencies.
The last phase in product development process is a detailed prototype test run. The Moventas design is always verified by type testing in our production facilities. Tests are conducted to improve product reliability, but also to comply with ever stricter demands from today’s wind turbine manufactures and regulatory agencies. A massive amount of testing results are compared with the simulation results, which enables even more accurate simulations.
Extreme conditions testing
Moventas gear units are designed to withstand the most extreme weather conditions. In addition to wind gears’ conventional prototype testing, the company provides gearbox qualification with a reliability test under severe ambient conditions in the climate chamber (-40 to 80°C), on both sub-system and component levels. This includes simulation of extreme conditions as well as an accelerated endurance test at elevated loads.
In addition, we run tailor-made tests based on customer requirements.
Test field capacity
In its homebase in Finland, the company has an up to 8.5 MW test bench and a 3.8 MW test bench as well as a 1.5 MW and a 2.5 MW test bench. In Huddersfield, UK we also have an up to 10MW test field.In addition, the company supports a 650 kW load test bench in Germany, a 300 kW one in Big Spring, Texas, and a 2.2-MW bench in Portland, Oregon.
Moventas
www.moventas.com.
Filed Under: Gearboxes, News, Turbines